The present invention relates to a waterbed mattress and, more particularly, to a waterbed mattress which has internal vertical baffle means for reducing water wave action within the mattress.
Although waterbeds of various constructions have become extremely popular in recent years, many individuals have purchased waterbeds and have been dissatisfied with them. The water mattress, which is basically a non-form retaining bag filled to capacity with water, exhibits a resonant frequency phenomenon related to the size of the bag and the mass of the water. Many individuals find this resonant characteristic disruptive of sleep or other pursuits.
A waterbed mattress is supported on four sides. With the advent of waterbeds, a special frame structure was developed to support a water-filled mattress. Generally, the most commonly used structure includes a platform or pedestal which raises the height of the mattress to the level of a conventional bed. The pedestal may be of any structural design. Usually, commercial pedestals are somewhat smaller in dimensions than the mattress and the supporting frame. The waterbed frame, therefor, may extend beyond the pedestal as much as a foot on all four sides. The waterbed frame includes a decking board, which rests on the pedestal, and an upstanding frame structure that includes rails. A waterbed mattress is supported on the decking board and within the upstanding frame. The pedestal and frame combination provides a basic unit which can be used for contemporary or traditional decor.
The most popular mattress size is the queen size which measures 60.times.84 inches. A queen size waterbed mattress which is 9 inches deep will hold approximately 187 gallons of water. A person lying on a waterbed mattress which holds that much water will create a transverse wave action each time he shifts his body weight. Once the water is set into motion, a resonant frequency develops which strikes the sides of the supporting frame of the bed and returns in the opposite direction. Any continuous movement will cause a larger resonant frequency which would require several minutes to dissipate.
There have been prior attempts to alleviate the problem of resonant frequencies created from water wave action in waterbed mattresses. One of the most common solutions is to reduce the thickness or height of the waterbed mattress by cushioning it with foam pads. Tinnell, in U.S. Pat. No. 4,015,299, discloses such a waterbed construction. Even though the construction shown by Tinnell is intended to reduce resonant frequencies, it is highly likely that there will be a substantial amount of resonant frequency. Furthermore, the Tinnell construction requires the use of a substantial amount of foam padding, which increases the cost of the mattress.
Labianco, in U.S. Pat. No. 3,840,921, shows a waterbed mattress construction having a pair of parallel internal baffles which are joined to the interior top and bottom surfaces of the mattress. Each baffle extends for a major portion of the length of the mattress, and thereby forms separate parallel chambers within the mattress. The ends of the chambers are in intercommunication adjacent to the ends of the mattress. This baffle arrangement allows water in the mattress to swirl from one chamber to the next. While the use of baffles is superior to other solutions for reducing water wave action and the inherent resonant frequency associated therewith, the fact remains that baffles arranged parallel to each other with intercommunication at each end of the mattress will not arrest the wave action in a short period of time. The swirling water at each end of the mattress does not dampen the wave action. In fact, the transverse wave action in combination with the swirling water creates stresses on the baffles where they are joined to the interior top and bottom surfaces. Quite often these stresses pull the baffles loose from the mattress, thereby destroying the dampening effect and in many cases the mattress as well by tearing the top or bottom surface to which they are sealed. The Labianco baffle arrangement is intended to be used with a waterbed frame having inclined walls such that some of the wave action bulges the mattress over the end of the frame to take up some of the resonant frequency, which is entirely different from the present invention which uses a regular waterbed frame without inclined walls.
Carson et al, in U.S. Pat. No. 3,736,604, disclose a waterbed mattress including baffles suspended from the interior top surface. The baffles are bottom weighted to resist water wave action. The baffles also have holes to provide a restricted communication between the chambers formed by the baffles. The baffles run lengthwise and crosswise, with the crosswise baffles spaced between the lengthwise baffles. The Carlson et al baffle arrangement sets up relatively stationary walls across the mattress, since the crosswise baffles interfere with any movement of the lengthwise baffles. The baffles being weighted and suspended from the top interior surface of the mattress and having communication holes are limited in maintaining a smooth wiping action with the bottom interior surface, which wiping action is important in dampening any wave action in a short period of time.